666407 has 16 divisors (see below), whose sum is σ = 817152. Its totient is φ = 531360.

The previous prime is 666403. The next prime is 666427. The reversal of 666407 is 704666.

666407 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 666407 - 2² = 666403 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 666407.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7988 + ... + 8070.

It is an arithmetic number, because the mean of its divisors is an integer number (51072).

2⁶⁶⁶⁴⁰⁷ is an apocalyptic number.

666407 is a deficient number, since it is larger than the sum of its proper divisors (150745).

666407 is a wasteful number, since it uses less digits than its factorization.

666407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 666407 is about 816.3375527317. The cubic root of 666407 is about 87.3467030144.

The spelling of 666407 in words is "six hundred sixty-six thousand, four hundred seven".